Mini air pump

ABSTRACT

A mini air pump which includes a diaphragm, a bladder base provided with penetrating bladder holes and air inlet channels, a pump body having a valve seat and a pump cover, an air inlet valve, an air outlet valve, a relief valve and a preload member is revealed. The valve seat is stacked over the diaphragm. An exhaust chamber and a spring chamber are constructed by the valve seat and the pump cover. The valve seat has exhaust channels communicating with the bladder cavity. A communicating return channel is constructed by the diaphragm, the bladder base and the valve seat. The return channel is communicating with the air inlet channel but not communicating with the spring chamber. A spring of the preload member applies a preload to the relief valve. Thereby the relief valve acts more accurately and the mini air pump is more stable in use.

BACKGROUND OF THE INVENTION 1. Technical Field

The present invention relates to a pump, especially to a mini air pump.

2. Description of Related Art

In a conventional mini air pump in which valves and a pump body areintegrated, relief flows flow into the sprig chamber and directly act onthe spring. Under the influence of air pressure, the spring can't be setup stably in the spring chamber and this causes changes in the abuttingforce applied to the relief valve by the spring. Thereby accurateactuation of the relief valve within preset air pressure is unable to beensured.

Moreover, buzzing noises of the air flow are usually generated whenrelief flows are directly released to the atmosphere. Thus the operatingnoise of the mini air pump is increased to a certain extent.

Thus there is room for improvement and there is a need to provide anovel mini air pump which solves the above problems to some degree.

SUMMARY OF THE INVENTION

Therefore it is a primary object of the present invention to provide amini air pump in which a relief valve actuates accurately for preciseregulation of air pressure in objects to be inflated and overpressureprotection of the objects to be inflated.

The present invention provides a mini air pump which includes: adiaphragm which includes a plurality of bladders on one side of thediaphragm and each of the bladders having a bladder cavity with anopening toward the other side of the diaphragm; a bladder base whichincludes a plurality of air inlet channels and a plurality of bladderholes penetrating the bladder base in thickness direction while thediaphragm is attached to the bladder base and the bladders are passedthrough the bladder holes correspondingly; a pump body which includes avalve seat provided with a plurality of exhaust channels and stackedover the diaphragm, a pump cover stacked on the valve sea, an exhaustchamber and a spring chamber separated from each other and constructedby the valve seat and the pump cover, and a return channel constructedby the valve seat, the diaphragm, and the bladder base and communicatingthe valve seat, the diaphragm, and the bladder base with one another;the exhaust channels communicating with the bladder cavity while returnchannel communicating with the air inlet channel but not communicatingwith the spring chamber; an air inlet valve disposed in flowingdirection of air in the air inlet channel and used for communicating thebladder cavity with the air inlet channel in one-way manner; an airoutlet valve arranged in flowing direction of air in the exhaust channeland used for communicating the exhaust chamber with the bladder cavityin one-way manner; a relief valve mounted in the exhaust chamber forselectively communicating the return channel with the exhaust chamber;and a preload member mounted in the spring chamber and having at leastone spring which applies a preload to the relief valve.

The spring chamber is disconnected from both the exhaust chamber and thereturn channel to prevent the exhaust flow or the return flow fromflowing into the spring chamber. Thus the spring is quite stablypositioned in the spring chamber to ensure the abutting force applied tothe relief valve by the spring remains the same and the relief valve canact more accurately. Therefore the stability of the mini air pump duringblowing up of the objects to be inflated is increased.

Implementation of the present invention produces advantageous effectswhich are described in detail as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 is an explosive view of an embodiment according to the presentinvention;

FIG. 2 is a sectional view of an embodiment according to the presentinvention;

FIG. 3 is a sectional view of an embodiment viewed from another angleaccording to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The preferred embodiments of the present invention are described indetail as follows and the embodiments are shown in the figures, whereinthe same or similar reference numerals are used to refer to the same orsimilar elements having the same or similar functions. The embodimentsdescribed with reference to the figures are exemplary and explanatoryonly and are not restrictive of the invention.

Refer to FIG. 1, FIG. 2 and FIG. 3, a mini air pump 100 according to thepresent invention includes a diaphragm 10, a bladder base 20, a pumpbody 30, an air inlet valve 40, an air outlet valve 51, a relief valve52 and a preload member 70.

With reference of FIG. 1, FIG. 2 and FIG. 3, a plurality of bladders 11are disposed on one side of the diaphragm 10 (such as a lower side inFIG. 2) and each bladder 11 includes a bladder cavity 111 with anopening toward the other side of the diaphragm 10 (such as an upper sidein FIG. 2). The diaphragm 10 is a flexible member made of materials suchas rubber. The volume of the bladder cavity 111 can be increased ordecreased due to the bladder 11 being squeezed or stretched by anexternal force so as to pump air/gas in/out.

The bladder base 20 is used for supporting the diaphragm 10 and composedof a plurality of bladder holes 21 and a plurality of air inlet channels22. The bladder holes 21 are penetrating the bladder base 20 in thethickness direction of the bladder base 20. The diaphragm 10 is attachedto the bladder base 20 and each of the bladders 11 is inserted throughone of the bladder holes 21 correspondingly.

The air inlet channels 22 are used for delivering air/gas to the bladdercavity 111. The air inlet channel 22 can not only be disposed on thebladder base 20. For example, a part of the air inlet channel 22 isformed on the bladder base 20 while the rest part of the air inletchannel 22 is formed on the pump body 30. In this case, intake air flowfirst is passed through the air inlet channel 22 of the bladder base 20,moved upward through the air inlet channel 22 of pump body 30 and thenturned downward to be sucked into the bladder cavity 111. In thisembodiment, the flow noise is reduced by the air flow travellingfurther.

In order to prevent backflow of the air in the bladder cavity 111, theair inlet valve 40 is disposed in the flowing direction of the air inthe air inlet channel 22 and used for communicating the bladder cavity111 with the air inlet channel 22 in one-way manner. More specifically,the air inlet valve 40 is open and the air is passed through the airinlet channel 22 to be delivered into the bladder cavity 111 when thebladder cavity 111 is stretched to increase the volume thereof and drawthe air in. While the bladder cavity 111 is squeezed to decrease thevolume thereof and exhaust the air, the air inlet valve 40 is closed.Thus arrangement of the air inlet valve 40 in the flowing direction ofthe intake flow is to prevent the air flow from flowing back.

Moreover, the pump body 30 consists of a valve seat 31 and a pump cover32 stacked on each other. The valve seat 31 is stacked over thediaphragm 10. The pump body 30 is generally made of plastic which iseasy to mold.

More specifically, as shown in FIG. 2 and FIG. 3, an exhaust chamber 33and a spring chamber 34, separated from each other, are constructed bythe valve seat 31 and the pump cover 32. The valve seat 31 is providedwith a plurality of exhaust channels 311 which are communicating withthe bladder cavities 111. When the bladder cavity 111 is compressed, theair in the bladder cavity 111 is flowing into the exhaust chamber 33through the exhaust channel 311 while exhaust flow will not flow intothe spring chamber 34.

In order to prevent air flow in the exhaust chamber 33 from returning,the air outlet valve 51 is disposed in the flowing direction of the airin the exhaust channel 311 and used for communicating the bladder cavity111 with the exhaust chamber 33 in one-way manner. More concretely, theair outlet valve 51 is closed and the air is delivered to the bladdercavity 111 through the air inlet channel 22 when the bladder cavity 111is stretched to increase the volume thereof and draw the air in. Whilethe bladder cavity 111 is squeezed to decrease the volume thereof andexhaust the air, the air outlet valve 51 is open and the air flow movesout through the exhaust channel 311. Moreover, the air outlet valve 51is open when the air inlet valve 40 is closed while the air outlet valve51 is closed once the air inlet valve 40 is open. Thereby the air isdrawn into the bladder cavity 111 and exhausted from the bladder cavity111 repeatedly.

A return channel 35 is constructed by the valve seat 31, the diaphragm10, and the bladder base 20 and communicating the valve seat 31, thediaphragm 10, and the bladder base 20 with one another. The returnchannel 35 is communicating with the air inlet channel 22 but is notcommunicating with the spring chamber 34. The relief valve 52 is mountedin the exhaust chamber 33 for selectively communicating the exhaustchamber 33 with the return channel 35. When the mini air pump 100 isused to blow up objects users intend to inflate and the pressure in theobject is over the preset value, the relief valve 52 is open and air inthe exhaust chamber 33 is output through the return channel 35 andreturned to the air inlet channel 22.

As shown in FIG. 2 and FIG. 3, the preload member 70 which includes atleast one spring 71 is mounted in the spring chamber 34. The spring 71applies a preload to the relief valve 52. The air flow in the exhaustchamber 33 will not flow into the spring chamber 34 because that theexhaust chamber 33 and the spring chamber 34 are separated from eachother. The air flow in the return channel 35 also won't flow into thespring chamber 34. Thus the spring 71 will not shake or shift due to therelief flow or the exhaust flow. Thereby the assembly position of thespring 71 in the spring chamber 34 remains and the same abutting force(the above preload) is applied to the relief valve 52 by the spring 71.Therefore accurate actuation of the relief valve 52 is ensured and thestability of the mini air pump 100 during the blowing-up is improved.

In a nutshell, in the mini air pump 100, the spring chamber 34 is notonly disconnected from the exhaust chamber 33 but also the returnchannel 35 so as to prevent the exhaust flow or the return flow fromflowing into the spring chamber 34. Thus the spring 71 is relativelystably positioned in the spring chamber 34 to ensure that the abuttingforce applied to the relief valve 52 by the spring 71 remains the sameand the relief valve 52 can actuate more accurately. Therefore thestability of the mini air pump 100 during the blow-up of the objects tobe inflated is increased.

Furthermore, noise caused by air flow can be reduced due to the returnflow being exhausted to the air inlet channel 22, instead of beingdirectly released to the atmosphere. And the operating noise of the miniair pump 100 is further minimized.

In some embodiments of the present invention, the air outlet valve 51and the relief valve 52 are integrally formed on a valve membrane 50, asshown in FIG. 1 together with FIG. 2 and FIG. 3. That means the airoutlet valve 51 and the relief valve 52 are integrated with the valvemembrane 50. The valve membrane 50 is clipped between the valve seat 31and the pump cover 32. The air outlet valve 51 is used to control on/offof the exhaust channels 311 while the pressure of the air in the exhaustchamber 33 is regulated through the relief valve 52. Thus the regulationof the blow-up of the objects to be inflated by the mini air pump 100 isachieved.

More specifically, the relief valve 52 is formed on one side of thevalve membrane 50 facing the valve seat 31. The valve seat 31 isprovided with a groove 312 while the valve membrane 50 is provided withat least one communication hole 53 by which the groove 312 and theexhaust chamber 33 are communicating with each other. The air flow inthe exhaust chamber 33 can flow to the groove 312 through thecommunication hole 53. When the relief valve 52 is open, the air flowmoves from the groove 312 to the return channel 35. Thereby pressurerelief is achieved.

As shown in FIG. 1, the groove 312 includes a circular groove 3121 and aplurality of long grooves 3122 which are arranged around and radiatedfrom the circular groove 3121. A free end of the long groove 3122 isarranged corresponding to the communication hole 53. As shown in FIG. 2and FIG. 3, the return channel 35 is located at a central portion of thepump body 30 while the exhaust chamber 33 is located around the pumpbody 30. The air flow in the exhaust chamber 33 is directed to thecentral circular groove 3121 through the long grooves 3122. Then the airflow is output through the return channel 35 when the relief valve 52 isopen.

As shown in FIG. 2 and FIG. 3, the relief valve 52 is a circular flangewhich is arranged around an entrance of the return channel 35 and isdirectly abutting against the valve seat 31. The spring 71 of thepreload member 70 is abutting against the valve membrane 50 so that thecircular flange is tightly attached to the valve seat 31. When the airpressure in the exhaust chamber 33 is insufficient to push and open therelief valve 52, the groove 312 and the return channel 35 are notcommunicating with each other. While the air pressure in the exhaustchamber 33 is larger than the abutting force of the spring 71, therelief valve 52 is moved upward so that the circular flange and theattached surface of the valve seat 31 are separated from each other toallow the groove 312 and the return channel 35 communicating with eachother.

In a preferred embodiment, as shown in FIG. 1 and FIG. 3, a positioningrod 54 is mounted on the other side of the valve membrane 50. Thepreload member 70 further includes a spring seat 72 and a stopper 73.The positioning rod 54 is inserted through the spring seat 72 and oneend of the spring 71 is abutting against and mounted in a limit slot 721defined in the spring seat 72. The spring seat 72 is positioned on thevalve membrane 50 by the positioning rod 54. The spring 71 is locked inthe limit slot 721 and applying an abutting force to the spring seat 72so that the relief valve 52 is further abutting against the valve seat31. That means the spring 71 and the valve membrane 50 are connectedfirmly by the spring seat 72 in combination with the positioning rod 54.

In another preferred embodiment, refer to FIG. 1 and FIG. 3, a guidingchamber 321 communicating with the spring chamber 34 is formed in thepump cover 32 and the other end of the spring 71 is extended into theguiding chamber 321 while the stopper 73 which applies a pre-tension tothe other end of the spring 71 is mounted in the guiding chamber 321.The two ends of the spring 71 is limited between the spring seat 72 andthe stopper 73 while the cylindrical surface of the spring 71 is limitedin the guiding chamber 321 for preventing shaking or weaving of thespring 71. The stability of the preload member 70 within the springchamber 34 is further improved.

As shown in FIG. 1 and FIG. 3, in a preferred embodiment of the presentinvention, the bladder base 20 is further provided with a plurality ofsink slots 23 each of which is communicating with the air inlet channel22 and the return channel 35 correspondingly. By the sink slots 23, thereturn flow is dispersed and delivered into different air inlet channels22 to prevent the return flow from concentrating in and flowing out fromthe return channel 35 on the bladder base 20. Thereby air flow noise isfurther reduced.

As shown in FIG. 2 and FIG. 3, in a preferred embodiment of the presentinvention, a valve cap 80 is disposed over the pump cover 32 and abuffer chamber 81 is constructed by the pump cover 32 and the valve cap80. The buffer chamber 81 is communicating with the exhaust chamber 33.That means the air flowing out from the exhaust chamber 33 is reachingthe buffer chamber 81 first, not being directly delivered to the objectto be inflated. Thereby the air flow is delivered to the outside afternoise attenuation in the buffer chamber 81. Therefore the operatingnoise of the mini air pump 100 is further reduced.

In order to avoid the air flow returning to the exhaust chamber 33, aone-way valve 90 is arranged at an air vent of the valve cap 80 or thepump cover 32. The one-way valve 90 is open when air in the exhaustchamber 33 is delivered to the outside. While the air in the exhaustchamber 33 is not delivered to the outside, the one-way valve 90 isclosed.

In some other embodiments of the present invention, the air inlet valve40 is integrally formed on the diaphragm 10 and arranged correspondingto an outlet of the air inlet channel 22. That means the air inlet valve40 is a part of the e diaphragm 10. When the air is delivered into thebladder cavity 111, the intake air flow first is directly passed throughthe air inlet channel 22 of the bladder base 20 to be sent into thebladder cavity 111.

It should be understood that terms such as “top”, “bottom”, “in”, “out”,“upper”, “lower”, etc. should be constructed to refer to the orientationas then described or as shown in the drawings. These relative terms arefor convenience of description and do not require that the presentinvention to constructed or operated in a particular orientation.

In the present invention, unless specified or limited otherwise, theterms “mounted”, “coupled”, “connected”, “fixed” and the like are usedbroadly and may be, for example, fixed connections, detachableconnection, or integral connection; may also be mechanical or electricalconnections; may also be direct connections or indirect connections viaintervening structures; may also be inner communications or interactionof two elements, which can be understood by those skilled in the artaccording to specific situations.

In the present disclosure, unless specified or limited otherwise, thefirst feature “on” or “under” the second feature may include directcontact of the first and second features, and may also include the firstand second features are not in direct contact but through additionalfeatures between them. Moreover, the first feature is “on”, “over” and“above” the second feature means the first feature directly is right onthe top of or diagonally above the second feature, or merely indicatingthat the first feature is at a higher level than the second feature. Thefirst feature is “beneath”, “under” and “below” the second feature meansthe first feature is directly is just beneath or diagonally below thesecond feature, or merely the first feature is at a lower level than thesecond feature.

In the description of the present specification, the description withreference to the term “one embodiment”, “some embodiments”, “anexample”, “a specific example”, or “some examples” etc., means thatparticular features, structures, materials, or characteristics of thedescribed embodiment is included in at least one embodiment or exampleof the present invention. In the present specification, the schematicdescription related to the above term is not necessary for the sameembodiment or example. Furthermore, the particular features, structures,materials, or characteristics described may be connected in at least oneembodiment or example in a suitable manner.

The above description is only the preferred embodiments of the presentinvention, and is not intended to limit the present invention in anyform. Although the invention has been disclosed as above in thepreferred embodiments, they are not intended to limit the invention. Aperson skilled in the relevant art will recognize that equivalentembodiment modified and varied as equivalent changes disclosed above canbe used without parting from the scope of the technical solution of thepresent invention. All the simple modification, equivalent changes andmodifications of the above embodiments according to the materialcontents of the invention shall be within the scope of the technicalsolution of the present invention.

What is claimed is:
 1. A mini air pump comprising: a diaphragm whichincludes a plurality of bladders on one side of the diaphragm and eachof the bladders having a bladder cavity with an opening toward the otherside of the diaphragm; a bladder base which includes a plurality of airinlet channels and a plurality of bladder holes penetrating the bladderbase in thickness direction while the diaphragm is attached to thebladder base and the bladders are passed through the bladder holescorrespondingly; a pump body which includes a valve seat provided with aplurality of exhaust channels and stacked over the diaphragm, a pumpcover stacked on the valve sea, an exhaust chamber and a spring chamberseparated from each other and constructed by the valve seat and the pumpcover, and a return channel constructed by the valve seat, thediaphragm, and the bladder base and communicating the valve seat, thediaphragm, and the bladder base with one another; the exhaust channelscommunicating with the bladder cavity while return channel communicatingwith the air inlet channel but not communicating with the springchamber; an air inlet valve disposed in flowing direction of air in theair inlet channel and used for communicating the bladder cavity with theair inlet channel in one-way manner; an air outlet valve arranged inflowing direction of air in the exhaust channel and used forcommunicating the exhaust chamber with the bladder cavity in one-waymanner; a relief valve mounted in the exhaust chamber for selectivelycommunicating the return channel with the exhaust chamber; and a preloadmember mounted in the spring chamber and having at least one springwhich applies a preload to the relief valve.
 2. The mini air pump asclaimed in claim 1, wherein the air outlet valve and the relief valveare integrally formed on a valve membrane while the relief valve isformed on one side of the valve membrane facing the valve seat; a grooveis mounted on the valve seat and the valve membrane is provided with atleast one communication hole by which the groove and the exhaust chamberare communicating with each other.
 3. The mini air pump as claimed inclaim 2, wherein the relief valve is a circular flange which is arrangedaround an entrance of the return channel and is directly abuttingagainst the valve seat.
 4. The mini air pump as claimed in claim 2,wherein the groove includes a circular groove and a plurality of longgrooves which are arranged around and radiated from the circular groovewhile a free end of the long groove is arranged corresponding to thecommunication hole.
 5. The mini air pump as claimed in claim 2, whereina positioning rod is mounted on the other side of the valve membranewhile the preload member further includes a spring seat and thepositioning rod is inserted through the spring seat; one end of thespring is abutting against and mounted in a limit slot defined in thespring seat.
 6. The mini air pump as claimed in claim 5, wherein aguiding chamber communicating with the spring chamber is formed in thepump cover and the other end of the spring is extended into the guidingchamber while a stopper which applies a pre-tension to the other end ofthe spring is mounted in the guiding chamber.
 7. The mini air pump asclaimed in claim 1, wherein the bladder base is further provided with aplurality of sink slots each of which is communicating with the airinlet channel and the return channel correspondingly.
 8. The mini airpump as claimed in claim 1, wherein a valve cap is disposed over thepump cover and a buffer chamber is constructed by the pump cover and thevalve cap; the buffer chamber is communicating with the exhaust chamber.9. The mini air pump as claimed in claim 8, wherein a one-way valve isarranged at an air vent of the valve cap or the pump cover.
 10. The miniair pump as claimed in claim 1, wherein the air inlet valve isintegrally formed on the diaphragm and arranged corresponding to anoutlet of the air inlet channel.